Session 2: Histopathology and Imaging in CAD - Intravascular Imaging: IVUS & OCT – Eun-Seok Shin

Intravascular Imaging and DCB Treatment in Coronary Artery Disease

Introduction to Intravascular Imaging

• The speaker introduces the topic of intravascular imaging (IUCT) and its impact on drug-coated balloon (DCB) treatment for coronary artery disease.

• Highlights that intravascular imaging-guided stent percutaneous coronary intervention (PCI) results in lower target vessel failure rates compared to angiographic-guided PCI, especially in complex cases.

Role of Intravascular Imaging in DCB Procedures

• Emphasizes that despite DCB being a balloon-based procedure, intravascular imaging is crucial for optimal preparation, balloon sizing, and complication prevention.

• Discusses a case study involving a 55-year-old patient with stable angina and challenges faced during revascularization using small balloons.

Challenges in Achieving Optimal Results

• Describes the use of intravascular ultrasound (IVUS), revealing negative remodeling and significant plaque burden at the distal portion of the artery.

• Notes difficulties encountered while attempting adequate results through repeated balloon angioplasty.

Successful Preparation Techniques

• The speaker discusses upsizing to larger scoring balloons for better vessel preparation, achieving successful resolution of focal stenosis.

• After DCB treatment, emphasizes the relationship between final minimal lumen diameter and follow-up outcomes; highlights need for aggressive region preparation.

Long-term Outcomes Post DCB Treatment

• Discusses how different vascular remodeling occurs based on dissection degree; notes type B dissections can lead to improved lumen dilation over time.

• Explains that minimal intimal dissection correlates with lumen enlargement post-treatment; challenges posed by fibrous plaques are also noted.

Comparative Analysis of Guidance Techniques

• Compares IVUS guidance versus angiography; finds IVUS tends to achieve larger pre-balloon sizes leading to better outcomes.

• Mentions ongoing investigations into plaque stability after DCB treatment using data from a real-world registry study conducted in Korea.

Study Findings on Lumen Area Changes

• Reports significant increases in mean lumen area post-treatment; details analysis methodology involving cross-sectional measurements at intervals.

Analysis of DCB Treatment Outcomes

Changes in Atheroma Composition

• The analysis revealed significant changes in atheroma composition post-DCB treatment, with over 60% of the atheroma changing to DK fiber.

• Notably, 19% transitioned to tinker fibroma and another 19% shifted to fibrous plaque.

Healing Process Observations

• Corresponding optical imaging indicated severe dissection had occurred, but healing was evident as multiple dissection plaques disappeared.

• Lipid levels decreased from 150° to 130°, while thickness increased from 110 micrometers to 150 micrometers after nine months.

Plaque Burden and Vessel Dynamics

• Post-treatment data showed a gross decrease in plaque burden and an increase in minimal luminal area, indicating stabilization of the phenotype.

• Three-year follow-up images displayed improved healing characteristics, with more rounded shapes observed in healed areas.

Role of Intravascular Imaging

• Intravascular imaging plays a crucial role in DCB procedures by ensuring adequate region preparation and understanding vessel healing dynamics without scaffolding.